<html>

<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>websocket</title>
</head>

<body>
	Welcome
	<br />
	<input id="text" type="text" />
	
	<button onclick="send()">发送消息</button>
	<hr />
	<button onclick="closeWebSocket()">关闭WebSocket连接</button>
	<hr />
	<div id="message"></div>
	
	<script type="text/javascript">
		var websocket = null;
		//判断当前浏览器是否支持WebSocket  
		if ('WebSocket' in window) {
			websocket = new WebSocket("ws://localhost:8080/blackA/websocket");
		} else {
			alert('当前浏览器 Not support websocket')
		}

		//连接发生错误的回调方法  
		websocket.onerror = function() {
			setMessageInnerHTML("WebSocket连接发生错误");
		};

		//连接成功建立的回调方法  
		websocket.onopen = function() {
			setMessageInnerHTML("WebSocket连接成功");
		}

		//接收到消息的回调方法  
		websocket.onmessage = function(event) {
			setMessageInnerHTML(event.data);
		}

		//连接关闭的回调方法  
		websocket.onclose = function() {
			setMessageInnerHTML("WebSocket连接关闭");
		}

		//监听窗口关闭事件，当窗口关闭时，主动去关闭websocket连接，防止连接还没断开就关闭窗口，server端会抛异常。  
		window.onbeforeunload = function() {
			closeWebSocket();
		}

		//将消息显示在网页上  
		function setMessageInnerHTML(innerHTML) {
			document.getElementById('message').innerHTML += innerHTML + '<br/>';
		}

		//关闭WebSocket连接  
		function closeWebSocket() {
			websocket.close();
		}

		//发送消息  
		function send() {
			var message = document.getElementById('text').value;
			websocket.send(message);
		}
	</script>
</body>

</html>